Google Erath在石油勘探中的应用

从网上下载的Google Earth卫星遥感照片更接近实际地形，在石油勘探初期，经常用它对工区进行踏勘和施工设计。文中详细地介绍了利用Google Earth进行施工设计的方法和步骤。     

The feature-based posterior crown design in a dental CAD/CAM system

This paper presents a newly developed CAD approach for a quick and accurate design of a dental posterior prosthesis. The approach arises from the basic idea that every human tooth has its own specific features. Based upon the features of the standard posterior tooth, the initial data containing the defined feature points are firstly acquired from the scanned points of the standard tooth. The standard prosthetic profile is thereby formulated using the bicubic Nurbs surface fitting technique. This profile has the two functions of possessing the same features with the patient’s missing posterior tooth, and the adjustability with the feature points and the defined B-spline profile feature curves. For the purpose of the adjustment of the established model, the global and occlusal feature curves are proposed considering the individual patient’s original information. According to these curves, the corresponding standard prosthetic profile is locally adjusted to meet the fit of the global size and occlusal surface. Finally, a close and continuous profile of a posterior crown is generated. Using this design, a posterior prosthesis is successfully manufactured in the computer-aided machining process.     

压裂斜井时射孔处雁形裂缝产生及干扰分析

在已射孔的斜井压裂过程中，射孔孔眼处会出现一系列的几乎相互平行的雁形裂缝。这些裂缝的延伸、连接受到地层应力及裂缝本身的影响，情况较为复杂，但它们的延伸和连接对压裂的成功与否至关重要。笔者对裂缝模型进行简化，将复变函数理论与位错理论相结合，并且考虑了裂缝表面有流体压力作用且裂缝之间存在相互干扰的情况下，建立了无限大介质中裂尖应力强度因子的数学模型，利用该模型可对雁型裂缝之间的相互干扰进行力学分析。应用数值方法对所建立的数学模型求解，得到裂尖的应力强度因子及转角，来预测裂缝连接情况。该结果可用来指导压裂井的射孔施工。     

丝织生产中对罗纹筒的防除浅析

罗纹筒是织绸生产厂准备工序常见主要疵点之一。笔者通过对生产现场实际观察分析认为：翻丝机、络丝机的摩擦滑移、挡车工操作不当、温湿度不合适等是产生罗纹筒的主要原因。下面就罗纹筒的产生和预防谈一些粗浅认识。     

FE Simulation for Internal Inversion of Aluminium Alloy Tube

1 Introduction A double-walled invertube is difficult to fabricate other than applying inversion process. Such kind of invertube can be used as impact energy absorbing element in transport vehicles, like aircrafts and automobiles. Reddy T Y[1] did the analysis of Internal inversion and calculated the inversion load. Reid[2] et al. examined nosing and internal inversion of cold drawn steel tube by the finite element package ABAQUS. Recently, Rosa P A[3] et al. investigated Internal invers…     

由苏州走向世界--访纽威阀门总经理助理姚炯先生

不久前在上海举办了ValveW orld2005亚洲研讨会和博览会，NEWAY阀门是此次世界阀门盛会的最大赞助商，请问NEWAY力争成为该会议的最大赞助商与贵公司“五年内成为世界级阀门制造商”的目标是否相关?     

企业间的商战模型分析

针对日益激烈的市场竞争，探讨了引发大规模商战的原因，建立了两企业集团间的商战模型，并分析了模型的均衡点，同时在此基础上建立了多个企业集团问商战模型，分析了模型的稳定性，最后根据模型的结论给出了企业间避免恶性商战的相关建议与对策。     

影响土壤中PAHs降解的环境因素及促进降解的措施

土壤中的多环芳烃(PAHs)类有机污染物的生物有效性低,不易降解。本文综述了影响污染土壤中多环芳烃降解的环境因素和促进降解措施的研究进展。影响土壤中多环芳烃降解的因素,包括水分、养分、土壤物理条件等;促进土壤中多环芳烃降解的措施有:向污染土壤添加有机溶剂、利用冯顿反应、添加堆肥和有机物料等。从目前研究来看,应当通过促进多环芳烃从土壤上解吸和培育具有较高多环芳烃降解能力的微生物来促进多环芳烃污染土壤的修复。     

The critical pressure and impeding pressure of Al evaporation during induction skull melting processing of TiAl

In this article, two key pressures, the critical pressure P _crit and the impeding pressure P _impe of elemental evaporation, are defined and studied based on the calculation relationship between the evaporation loss rate N _m and the chamber pressure P during melting of titanium-aluminum alloys. When the chamber pressure is below P _crit or above P _impe, N _m tends to the maximum or the minimum value and remains almost unchanged. However, if P _crit<P<P _impe, with the increase of the chamber pressure, N _m declines sharply. A method has been put forward to calculate P _crit and P _impe of Al evaporation in a Ti-XAl (at pct) (X=25 to 50) melt. The calculation result shows that P _crit or P _impe is a second-order function of the molar percentage of Al and the melt temperature.